Paediatric A and P Flashcards
Anatomy
Large tongue
Soft floor of mouth
Horseshoe shaped epiglottis. soft and floppy
High, anterior larynx, positioned at C3-C4
Larynx is funnel shaped in <8yr
Cricoid ring is narrowest part of airway
Trachea short and soft
Symmetry or carinal angle
what type of laryngoscope blade for infants?
Straight blade
airways increase from birth to adulthood by?
10 times
Lungs
smaller upper and lower airways
distal airways are narrower and easily obstructed
At birth only 1/6 of alveoli present. Alveoli cluster develop over first 8 years of life.
Air alveolar interface is 3m2 at birth compared to 70m2 in adults
Ribs
horizontal in infants
therefore contributes less to chest expansion and increases tidal volume.
Chest wall
Thinner and less muscular
Less slow twitch muscle fibre means prone to respiratory fatigue. Pre term infants have even less.
Less subcutaneous fat makes auscultation easier to hear
Absorb higher traumatic impact as its more pliable, may be underlying damage with no significant external injuries.
Diaphragmatic breathing
Intercostals are weak and ineffective.
Diaphragm is dominant for ventilation.
muscles build and ribs ossify as child develops creating a stronger structure.
Poor carbohydrate stores
Use glucose stored in liver, therefore hypoglycaemia can be a problem.
Abdominal distention
Can be due to weak abdominal wall muscles and size of organs.
Liver extends below the rib cage in infants and is therefore susceptible to injury.
Anatomy for breathing overview
Small upper and lower airways. <12yrs obligate nasal breathers.
Immature lungs
Horizontal ribs
Compliant chest wall
Diaphragmatic breathing
More prone to respiratory failure
Vulnerable abdominal contents
Slight blockage of nasal passages
Can reduce breathing capacity in 0-6 months:
Easily blocked by secretion.
Small airways have an increased susceptibility to infection and oedema.
URTI’s are one of the most common reasons for paediatric presentation.
Adenotonsiilar hypertrophy (AH)
Caused by recurrent or chronic infections, leading to AH
Can be worsened by URTI’s
Can cause:
Difficulty feeding small children.
Mouth breathing.
Noisy respirations.
Stridor.
Loud snoring and sleep apnea.
Ventricular size
At birth ventricles are similar size and weight, but Right side is dominant.
by 4-6 months the Left ventricle is dominant.
Blood volume
newborn: 80 ml/kg
decreases with age to 60-70 ml/kg
NB. 125ml of blood loss form cord is 50% blood loss
Increased Respiratory Rate
Higher metabolic rate.
Greater O2 consumption.
Signs of respiratory distress
Recession.
Abdominal breathing.
Nasal flaring.
Grunting.
NB. chest recession in a child >6yr shows significant illness.
Circulation
Stroke volume relatively fixed until two years.
Respond to shock with tachycardia.
Cardiac output related to pulse rate.
Less able to respond to fluid resuscitation.
Cardiovascular emergencies are relatively rare.
NB. <2yr old bradycardia can be a sign of imminent cardiorespiratory arrest.
Thermoregulation
Brown fat used for heat production in first year of life.
Depletion coincides with the kicking in of the shivering reflex.
Deposits around kidneys, neck and upper chest.
Metabolic acidosis may result from hypothermia as not enough gas exchange for the work that’s being done. Hypothermia may indicate sepsis in the newborn.
Body proportions - Body Surface Area (BSA)
BSA to weight ratio:
Decreases with age.
Small children with a high ratio lose heat quicker.
high BSA increases risk of hypothermia due to potential for rapid heat loss.
Hypoglycaemia
Not only present in diabetics
A reaction to stress
Poor glycogen stores coupled with high metabolic rate
When are we going to BM test children?
Seriously unwell, prolonged seizure, altered consciousness.
Can be due to patient being cold and brown fat metabolism causing reduced glucose levels.
NB. don’t give DKA children fluids UNLESS they have hypovolaemic shock. Fluids can cause cerebral oedema if given too fast.
Intra abdominal organs
Closer proximity to each other.
Liver and spleen may extend below the costal margin.
Bladder extends higher out of pelvis.
Kidneys more anterior and not protected as well as adults due to compliant chest wall and immature abdominal muscles.
Less fat and muscle to protect organs.
Renal systems
Renal blood flow and glomerular filtration are low in the first two years of life due to high renal vascular resistance.
Liver function
Initially immature with decreased function of hepatic enzymes.
Barbiturates and opioids have a longer duration of action due to the slower metabolism.
Psychology
Communication
Parental involvement
Age regression - when sick 5yr could act like 3yr old.
Fear/pain/guilt
